1. Field of the Invention
The present invention relates to a mechanism which controls a direction of air flow from an outlet of an air-conditioning unit.
2. Description of the Related Art
FIGS. 60-62 show the air-directing control mechanism in a conventional air conditioning unit as disclosed in the unexamined Japanese Utility Model Publication No. Sho-58-69735. FIG. 60 shows the body of an air-conditioning unit, FIG. 61 shows a cross section of the body of FIG. 60, and FIG. 62 shows a vertical section of the body of FIG. 60.
In the figures, the reference numeral 1 represents the body of an air conditioning unit, 2 represents a front panel having an air inlet 3 which covers the front surface of the body 1, 4 represents an air-outlet having an opening at a front lower portion of the body 1, 5 represents a heat exchanger oriented so as to face air inlet 3, 6 represents a casing which is situated inside of the main body 1 which enables an air course 13 to be formed, 7 represents a movable vane situated close to the air outlet 4 and is pivotally mounted to the left and right side walls 11 and 15 of the front panel to by a shaft 16 which is mounted to the left and right end portions of the air-outlet 4. Movable vane 7 changes the air direction both horizontally, vertically, or any combination of these directions. Reference numeral 8 represents a series of parallel guide vanes which run between walls 10 and 14 of the left and right side portions of an air outlet nozzle 9 so as to be held by a pivotal shaft 17 and to change the air direction from the left side to the right side, 9 represents an air outlet nozzle and is positioned under the inner casing 6 to thereby provide an air course, 12 represents a line flow fan located on the air course 13 before the air outlet 4 and is driven by motor 18, and 19 represents coiled springs suspended from the shaft 16.
FIG. 63 shows the layout of the right guide vanes depicted in FIG. 62, and FIG. 64 shows one of the guide vanes depicted in FIG. 63.
In the figures, the reference numeral 20 represents left/right movable rod which is pivotally mounted to the row of guide vanes 8 by shafts 21. This rod enables the angles of the guide vanes 8 to be simultaneously changed to an arbitrary valve in either the left or right direction.
The operation of the apparatus will be described below. When the line flow fan 12 is driven in a conventional air conditioning unit constructed as described above, air is sucked from the room through the inlet 3, passes through the heat exchanger 5 and is cooled in a cooling mode or heated in a heating mode. The air is then drawn down the air course 13 as blown out to the room through the air outlet 4. This flow of air is represented by the arrow U in FIG. 61. The upward/downward air direction and the leftward/rightward air direction are adjusted by the movable vane 7 and the guide vanes 8, respectively. The shafts 21 that pivotally hold the guide vanes 8 and the leftward/rightward movable rod 20 are connected to the shaft 17 that pivotally holds the guide vanes 8. These are connected at intervals of a predetermined distance, enabling all of the guide vanes 8 to be turned in the same direction at the same time. This is controlled on the basis of the displacement quantity +A supplied to the leftward/rightward movable rod 20.
Due to design restrictions it is not possible to expose the movable vane 7 and the guide vanes 8 to the outside of the front panel 2. It is necessary to position the movable vane 7 to the outermost part of the air-outlet because this vane 7 must also serve as a blocking cover for the air outlet. Accordingly, the guide vanes 8 cannot be positioned further back from the air outlet than movable vane 7. In this case, the operation of the mechanism which controls the direction of air flow is as follows. For example, when the leftward/rightward movable rod 20 is moved to the right by a displacement quantity +A as shown in FIG. 63, the guide vanes 8 will direct the air to the right side. Air will then be reflected by the surface of the wall 14 and a forward straight air current will be formed before the air is blown out. In this case, the flow of air in the direction of the guide vanes is represented by W.sub.2 and the flow of air after reflection is represented by V.sub.2. The flow W.sub.2 is disturbed by the flow V.sub.2 so that it is deflected according to the vector representing the direction of (V.sub.2 +W.sub.2). As a result, the outlet air direction cannot be accurately controlled in a conventional air conditioning unit even in the case where the air direction is said to be at a left-rightwise oblique angle with respect to the air-conditioning equipment.
FIGS. 65 and 66 show another mechanism for controlling the direction of air in a conventional air-conditioning unit as described in Japanese Utility Model Unexamined Publication No. Sho-63-147650. FIG. 65 is a cross section of the apparatus and FIG. 66 shows the operating state of the apparatus depicted in FIG. 65. In the figures, the reference numeral 201 represents an air-outlet, 202 represents the inner wall of the air-outlet 201, and 203 represents two rows of vanes. These vanes are located at equal intervals and change the air direction.
The reference numeral 204 represents shafts which are connected to the vanes 203 and enable them to be connected to the inner wall 202.
The reference numeral 205 represents connection arms each of which connects the groups of vanes 203. Connection shafts 206 pivotally hold the other edge side of the arm with respect to shafts 204 of the vanes 203 are joined. As shown in FIG. 65, the connection shafts 206 are arranged in a line inclined with respect to a line connecting the respecter shafts 204 of the vanes 203 so that the distance between the shaft 204 of the vane 203 furthest from the inner wall 202 (inner vane) and the connection shaft 206 in FIG. 65 is said to be shorter than the distance between the shaft 204 of the vane 203 closest to inner wall 202 (outer vane) and the connection shaft 206 in FIG. 65.
The configuration of a mechanism for controlling the direction of air from a conventional air conditioning unit is shown in FIGS. 65 and 66 and has been described above. As shown in FIG. 66, this mechanism is used such that two groups of vanes 203 are arranged with their lower portions spread out. In this condition, the inclination of inner vane 203 in FIG. 66 is nearer to the horizontal line than the inclination of outer vane 203 in FIG. 66. Accordingly, the respective angles of blown air deflected by the vanes 203 are formed as represented by the solid arrows in FIG. 66 so that the inclination of the inner vane 203 is nearer to the horizontal line than the inclination of the outer vane 203.
Further, a narrow gap is formed at a center portion between the two groups of vanes 203. Accordingly, air 207 blow out through this gap cannot flow smoothly, so that the air flow 207 is weakened. As a result, secondary air 208 in the vicinity of the air 207 is entrained, so that a dew 209 is produced on the vanes 203.
As the air directing apparatus in conventional indoor units is configured as described above, in general blown air currents are deflected toward the front of the indoor unit. This resultant deflection can be attributed to the fact that the air flow is reflected from both the nozzles and from the right and left walls of the front panel. It becomes apparent that the resulting air current cannot be made to arrive accurately at the point aimed at. This occurs particularly when the blown air current is controlled by using a human body sensor so the direction of the air flow tracks a human's location.
In the aforementioned mechanism for controlling the direction of air flow, when the left/right deflection rod 20 is moved by a large displacement, the pressure loss caused by the guide vanes 8 increases so that the quantity of air blown out of the air-outlet 4 through the air course 13 is extremely reduced. As a result, particularly in an air heating mode, heated air is blown upwards so that the heated air cannot reach the floor of the living room.
As the temperature of the blown air is lowered in an air cooling mode, dew is deposited onto respective portions of the air-outlet 4 and the units body 1. This can result in dew droplets falling into the space being air conditioned and/or it can promote mildew growth. Further, more of the blown air falls down to the floor near the air-conditioning equipment rather than being blown in a forward direction as in the previous case. Accuracy in controlling an air currents direction is undoubtedly lowered.
Due to the fact that the air direction is primarily controlled by the guide vanes 8, the air current is separated so that dew is deposited onto respective parts of the air outlet 4 in an air cooling mode. Furthermore, in the case where the air conditioning equipment is positioned close to a wall on the conditioned space, the blown air currents are deflected on the wall so that this air current is sucked into the equipment through the suction inlet 3. Accordingly, the air current does not circulate in the living rooms so that a comfortable environment cannot be achieved.
In order to prevent the aforementioned problem, it is necessary to limit the deflection angle of the left/right air deflection plates. In conventional apparatuses this has been done, although this limited angle similarly limits the flow direction in an air heating mode when there is no dew deposition and also when the unit is not mounted near a wall. In these cases an uneven space temperature may result in a subsequent lack of comfort.
In the air directing mechanism used in conventional air-conditioning units as shown in FIGS. 65 or in 66, the respective vanes 203 are produced while the distances between the shafts 204 and the connection shafts 206 are successively changed in accordance with the positions of the arrangement of the vanes 203. The production and assembly of these vanes 203 requires lengthy labor time.
Furthermore, a narrow gap is formed between the two groups of vanes 203. Accordingly, the air 207 blown out through this gap is weak so that secondary air 208 in the close vicinity is entrained. Dew 209 will thus be deposited on the vanes 203 and eventually fall down into the space to be air-conditioned.
In addition, it is difficult to ensure that the vanes 203 at the pivotally mounted portions are able to move smoothly and noiselessly.